Personality diagnoses get overhaul

MICHIGAN STATE (US) — A new method of categorizing personality disorders could ultimately improve treatment, researchers say.

“We’re proposing a different way of thinking about personality and personality disorders,” says Christopher  Hopwood, assistant professor of psychology at Michigan State University.

“There’s widespread agreement among personality disorder researchers that the current way to conceptualize personality disorders is not working.”

The study is being cited by experts currently updating the Diagnostic and Statistical Manual of Mental Disorders—considered the bible of the mental health industry. The next edition is due to be released in 2013.

The study also will appear in an upcoming issue of the Journal of Personality Disorders.

The current method breaks personality disordes into 10 categories. That system is flawed, Hopwood says, because it does not take into account severity of personality disorders and often leads to overlapping diagnoses.

“It’s just not true that there are 10 types of personalities disorders, and that they’re all categorical—that you either have this personality disorder or you don’t,” says Hopwood, who proposes a three-stage strategy.

Stage One: Consider a patient’s normal personality traits, such as introversion/extroversion, that may also indicate patient strengths that could help in overcoming psychiatric difficulties.

“If a person is depressed and I’m a clinician, it might make a difference if I think they’re extroverted depressive rather than introverted depressive,” Hopwood says. “It may dictate the type of recommendations I make for them.”

Stage Two: Create a numerical score to represent severity of the disorder.

“We’re arguing that one single score can represent that severity, so clinicians can easily communicate with one another about how severe a patient is,” Hopwood says. “That may indicate decisions such as whether this person should be hospitalized or treated with outpatient care.”

Stage Three: Condense the list of 10 personality disorder categories to five dimensional ratings. Under this proposal, clinicians would diagnose how many symptoms of each disorder a patient has, rather than whether they have one or more of 10 disorders as in the current system.

Hopwood says this is more reliable, valid, and specific than the current system. He adds research has not sufficiently supported the validity of several current personality disorders.

The proposed dimensional ratings are:

  • Peculiarity. The defining characteristic here is oddness in thought or behavior. This dimension includes the diagnoses of paranoid, schizotypal, and schizoid.
  • Withdrawal. This includes avoidant personalities, including issues like not wanting to leave the house.
  • Fearfulness. This combines disorders with opposite extremes of harm avoidance, such as antisocial (which involves fearlessness) and dependant or avoidant (which involves fearfulness).
  • Unstable. This is similar to the diagnosis of borderline. The defining characteristic is instability, such as with relationships, identity, or emotional experience.
  • Deliberate. This includes obsessive-compulsive disorder and other disorders defined by overly methodical behavior. “It’s having a rigid sense of how life should happen—how I should behave and how other people should behave,” Hopwood says.

Ultimately, the proposal could improve both the system for diagnosing personality disorders as well as the outcome, Hopwood says. “Presumably, if this leads to better clinical efficiency it could lead to better clinical care, and that’s in everybody’s interest.”

Researchers from Columbia Medical School and Texas A&M University contributed to the proposal.

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